20809296989 has 16 divisors (see below), whose sum is σ = 23954724864. Its totient is φ = 17925283200.

The previous prime is 20809296979. The next prime is 20809296997. The reversal of 20809296989 is 98969290802.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20809296989 is a prime.

It is a super-2 number, since 2×20809296989² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20809296979) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 836477 + ... + 860994.

It is an arithmetic number, because the mean of its divisors is an integer number (1497170304).

Almost surely, 2^20809296989 is an apocalyptic number.

It is an amenable number.

20809296989 is a deficient number, since it is larger than the sum of its proper divisors (3145427875).

20809296989 is a wasteful number, since it uses less digits than its factorization.

20809296989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1697548.

The product of its (nonzero) digits is 10077696, while the sum is 62.

The spelling of 20809296989 in words is "twenty billion, eight hundred nine million, two hundred ninety-six thousand, nine hundred eighty-nine".